Refrigerant compressor structure



Aug. 13, 1935. J. R. REPLOGLE 2,011,079

I REFRIGERANT COMPRESSOR STRUCTURE h Filed June 6, 1952 7/ 756 INVENTOR do)??? 71. Perloyle.

BY mflfix WM ATTORNEY Patented Aug. 13, 1935 PATENT OFFICE REFRIGERANT COMPRESSOR STRUCTURE John R. Replogle, Detroit, Mich., assignor, by mesne assignments, to Copeland Refrigeration Corporation, Mount Cle tion of Michigan mens, Mich, a corpora- Application June 6, 1932, Serial No. 615,513 Claims. (Cl. 230-4630) This invention relates to mechanisms for compressing fiuids and has particular relation to the construction of the valves and other parts of such compressing mechanisms.

An object of the invention is to provide a simplified and eiiicient mechanism for compressing fluid such as the working fluid in refrigerating systems and in which the working parts are capable of operation at relatively high speeds to perform the functions thereof in response to extremely rapid variations in the pressure of the working fluids operated up pn.

Another object of the invention is to provide a refrigerant compressor having working parts capable of operation with the least possible amount of noise in order that. the mechanism will not be objectionable to the occupants of a home in which it is employed.

Another object of the invention is to provide a compressing mechanism having relatively light and inexpensive working parts such that their operation at relatively high speed will not create objectionable noises and vibrations which might otherwise result therefrom.

Another object of the invention is to provide compressor suction and discharge valves which will operate quietly and efliciently at high speeds and which are simple, light and durable enough to give efficient and reliable service in small, directly driven refrigerant compressors especially adapted for small refrigerating system purposes.

Another object of the invention is to provide refrigerant compressor valves which require little clearance space for their operation.

Another object of the invention is to improve the operational characteristics of ordinary disc valves when employed as suction and discharge valves in small refrigerant compressors.

Another object of the invention is to reduce the resistance to the flow of fluid both inwardly and outwardly of a compressor cylinder of which operation and high speed is required.

The embodiment of the invention disclosed herein for the purpose of illustration comprises a cylinder having an end portion thereof closed by a plate through which fluid compressed in the cylinder is discharged into a cylinder head enclosing the space thereabove. A- piston reciproeating in the aforesaid cylinder is provided with i a plurality of ports through the head thereof which are adapted to supply refrigerant vapor to be compressed within the cylinder when the piston moves downwardly therein. In order to prevent the escape of refrigerant through said ports on the upstroke of the piston the ports are closed by an annular disc valve secured at its center upon a movable pin, the movement of which is limited by a nut engaging a portion of the piston head. The valve plate, which also is provided with openings permitting the discharge of re- 6 frigerant from the cylinder upon the upstroke of the piston, is provided with a similar annular disc valve for automatically closing the port when the piston reaches the outer limit in its path of travel. This valve is held resiliently in position by a suitable spring within a cage secured upon the valve plate in any suitable manner. All portions of the aforesaid valve structure are constructed of extremely light and durable parts capable of operating without attention for long periods at comparatively high speeds. r

In the drawing:

Figure 1 illustrates a fragmentary vertical sectional view through a refrigerant compressor constructed according to the principles of the invention;

Fig. 2 is a horizontal sectional view through the compressor taken substantially on line 2-2 of Fig. 1;

Fig. 3 is a fragmentary horizontal view taken on line 3-3 of Fig. 1;

Fig. 4 is another fragmentary horizontal sectional view taken substantially upon line 4-4 of Fig. 1, and

Fig. 5 is a fragmentary vertical sectional view 30 of a slightly different form of compressor structure illustrating the principles of the invention.

Referring particularly to the drawing there is employed a compressor I 0 which may be of any sectional type desired although in the present instance a 5.

reciprocating type of compressor is disclosed for the purpose of illustration. Such compressor comprises principally a cylinder ll having therein a piston l2 provided with a piston pin l3 to which a connecting rod I4 is secured for driving the compressor piston in a reciprocating path of movement, from a crankshaft orother similar device (not shown). The crankshaft preferably is connected directly to a relatively small high speed motor for driving the piston at a corresponding rate to expel from the cylinder a large amount of gas in proportion to the size thereof. The upper end of the cylinder II is covered by a valve plate I6 which in turn has secured thereon by means of bolts I! a cylinder head I8 adapted to receive and to collect the high pressure gas delivered by the compressor.

The head IQ of the piston is provided with a centrally disposed opening in which is secured a compressor suction valve 2| which is adapted to open in response to the downward movement of the piston to admit gas to the region thereabove and to close upon the upward movement thereof to prevent the escape therethrough of the gas so admitted. The exterior surface of the piston head I9 is so recessed as to receive therebeneath an annular disc 22, the outer edge of which is adapted to rest upon an annular seat 23 formed in the recessed upper or head portion of the piston and engaging the lower surface of the disc.

The annular space 24 formed around the outside of the seat 23 communicates with the region above the piston l2 and below the valve plate It through a small clearance space formed between the piston and the outer edge of the disc 22. The annular space 26 inside the seat 23 communicates through a plurality of openings 21 with the inside of the piston l2 and the crankcase of the compressor which in turn is connected with an evaporating unit of a refrigerating system (not shown).

The inner periphery of the disc 22 rests upon the upper extremity of an annular boss 28 surrounding the opening in which the valve 2i is slidably disposed. The disc 22 is secured for operation within the piston head l9 between a relatively flat head 29 of a bolt 32 engaging the upper surface thereof and the upper extremity of a sleeve 3i slidably disposed within the boss 28 and secured upon an intermediate portion of the bolt by a nut 33 engaging the lower extremity thereof. The nut 33, which is threaded upon the bolt- 32, is permanently secured in position to prevent the loosening of the parts of the valve 2| by having the lower extremity of the bolt 32 projecting therebeyond enlarged or upset as is indicated at 34.

In order to provide for an appreciable movement of the valve 28 with respect to the piston l2 the sleeve 3! is made somewhat longer than the length of the boss 28 to provide on the upstroke of the piston a slight space between the boss and the nut 33. Thus when the piston reaches the upper limit of its stroke the inertia of the parts of the valve 2| tends to carry the valve onwardly until the nut 33 abuts the lower extremity of the boss 28. This movement of the valve bodily raises the disc 22 off the seat 23 and on the downstroke of the piston the low pressure gas within the compressor crank case flows through the ports 21, the annular space 26, between the annular seat 23 and the disc 22, and into the unoccupied space above the piston. When the piston reaches its downward limit of travel the cylinder is closed also by the inertia of the parts of the valve 2i which tends to seat the disc 22 upon the seat 23 at the beginning of the movement of the piston in the opposite direction. The valve thus seated prevents a return flow of the gas admitted to the cylinder from the crankcase whereupon the gas is compressed within the cylinder upon the movement of the piston in the opposite direction.

At the upper limit of travel of the piston i2 the head surface thereof and the upper surface of the disc 22 extends within close proximity to the lower surface of the valve plate iii. In order to prevent the bolt head 29 from striking against the valve plate the latter is provided with an opening 36 just large enough to admit the head without creating an excessive amount of clearance space within the cylinder.

Just above the outer extremity of the disc 22 are located a plurality of openings 31 formed in the valve plate it for the purpose of permitting the discharge of compressed gas from within the cylinder to the space within the head it. These openings or ports communicate with an annular opening 38 formed in the upper surface of the v valve plate it between a pair of annular seats 39 and M terminating at their upper extremities in approximately the plane of the upper surface of the valve plate 65. At the inner extremity of an annular opening d2 formed inside the annular seat M is a boss 33 around which is seated a flange 3 formed at the inner periphery of a relatively flat valve securing cage 36 of a compressor discharge valve M. The outer periphery of the cage is formed to provide-an annular rim t8 which terminate in an outwardly projecting flange 49 by which he cage is secured in position beneath the head IS in an annular recess 5| formed outside the annular seat 39.

Mounted on the outer surface of the flange 44 and beneath the cage 46 is an annular disc 52 the lower surface of which rests upon the upper extremities of theannular seating rings 39 and M. The disc is resiliently held in. position upon such rings by a spring 52 formed with an inner annular part 53 engaging the outer surface of the flange 44 and resting upon the upper surface of the disc 52. The outer periphery of such annular part terminates in a plurality of radially extending arcuate arms 54, the outer ends of which are adapted resiliently to engage the lower surface of the cage 46 in the vicinity of the rim 48 to hold the annular part 53 against the upper surface of the disc 52. The cage, 46, at the outer edge of the rim I8, is provided with a plurality of slots or openings 56 providing communication between the interior of the head I8 and the space below the cage.

When the gas is compressed within the cylinder upon the upstroke of the piston l2, as has been described hereinbefore, the disc 52 remains seated on the annular seats 39 and 49 until the gas within the cylinder reaches a pressure great enough to overcome the resilient force exerted by the spring 5i and the pressure of the gas within the head l8. Any further increase in the pressure within the cylinder then lifts the disc 52 off the seats 39 and M thus permitting compressed gas to flow from the cylinder through the ports 3i and the annular port 38, between the annular seat 39 and the lower surface of the disc '52, and outwardly from beneath the cage 36 through the slots 56.

When the piston reaches its upper limit of travel and all the excess gas is expelled from the cylinder ii the spring 55 then moves the disc 52 again into seating position upon the annular seats 39 and ti to close the cylinder against the return flow of gas from the head it! during the downward movement of the piston thereafter occurring.

The passages through both the piston head l9 and the valve plate Iii are large enough to permit the rapid flow of gas therethrough witliout creating excessive friction in so doing. Also the valve seats 23 and 39 in the piston head is and valve plate i6 respectively, are relatively large in diameter to provide a relatively large space between the seats and the discs 22 and 52 respectively, without excessive movement of the latter. The disx 22 and 52 preferably are made of spring material to insure quietness of operation of the valves although the discs are constructed to open. in response to the operation of the compressor without reliance upon the flexible quality thereof.

In the structure disclosed by Fig. 5 the valve plate l6 has the upper surface thereof cut out in such manner as tocreceive therebeneath the central portion of the aforesaid recess therein.

Beneath the cage 6|, there is provided sufficient space for the operation of a spring 64 and a disc 66, the latter of which rests upon a pair of annular seats 61 and 68 formed in the valve plate l6 around the boss 63. The construction of the spring 64 and disc 86 is very much like the construction of the spring and disc respectively employed in the structure previously described except that the disc 66'is relatively small in diameter compared with the spring 64 and consequently the force of the spring is applied to the disc in a region nearer the outer periphery thereof.

The suction valve 2| employed in this structure consists of a disc 69 disposed beneath the upper surface of the piston l2 and welded or otherwise secured to a tubular retaining member ll disposed slidably in an opening formed in the head of the piston l2. The outer edge of the disc 61 is supported upon an annular seat 12 formed in the head surface of the piston l2 and with the space inside of which the interior of thepiston communicates through arcuate slots 13 formed in that portion of the retaining member 1| adjacent which the disc 69 is secured. These slots not only provide ports for the ,pasage of gas through the piston I2 but serve" to prevent distortion of the disc by permitting expansion and contraction of the elements of the valve independently of one another. The lower extremity of the tubular retaining member H is provided with an outwardly projecting flange 14 which is spaced slightly below the lower extremity of the boss 28 formed in the piston head l9 and around the opening in which the tubular member H is slidably disposed.

In the operation of the structure the gas within the compressor flows through the ports 13 and over the annular seat 12 on the downward movement of the piston I! when the inertia of the valve causes the flange T4 to engage the lower extremity of the boss 28 after the reversal in movement of the piston. Thereafter upon the upstroke of the piston the disc 69 is seated upon the annular seat 12. When the gas contained within the cylinder is compresed sufficiently the disc 66 moves oil the seats 61 and 68-to permit the gas to escape to the interior of the head I8.

While the structure as herein disclosed constitutes a preferred form and application of the invention, it is to be understood that numerous modified and equivalent structure are within the scope of the invention as defined by the appended claims.

I claim:

1. The combination with a cylinder having a valve plate and a head secured thereon, said valve projection extending upwardly from a central portion thereof, of a cage disposed within said head upon said valve plate and having an opening formed therein for receiving the aforesaid plate projection, said cage also having an outwardly projecting flange secured in a recess between said head and valve plate and a valve secured between said valve plate and cage for controlling the flow of fluid through the former.

3 plate having a 2. The combination with a compressor having a valve plate and a head secured thereon, said valve plate having a pair of annular seats formed beneath the upper surface thereof, of an annular valve supported by said seats for preventing the flow of fluid inwardly of said compressor through openings formed in said valve plate, an arcuate spring disposed upon the upper surface of said valve for resiliently retaining the latter in position upon said seats, a cage for retaining said valve and spring in position, said cage having a laterally projecting annular flange formed at the center thereof and projecting within a recess formed in said valve plate, and a radial flange at the outer periphery thereof extending within a recess between said valve plate and head and con- -flned therein for securing the elements of the aforesaid valve structure in operative position.

3. The combination with a compressor having a valve plate and a head secured thereon, said valve plate having a recess formed in the surface thereof adjacent said head and extending beneath the inner edges thereof, of a substantially flat valve cage secured upon said valve plate with the edges thereof confined beneath said head, the major portion of said valve cage being disposed below the upper surface of said valve plate, and a compressor discharge valve confined beneath said valve plate for controlling the flow of working fluid operated upon by said compressor. a

4. In a compressor structure the combination of a cylinder, a valve plate, and a head secured thereon, said valve plate having a recess formed between said cage and valve plate, and a spring between said disc valve and valve cage for resiliently retaining said valve in position.

5. The combination with a cylinder, of a substantially flat valve plate and a head secured thereon, the upper surface of said plate being annularly recessed whereby .to provide an upwardly extending projection centrally thereof, a pair of spaced and concentric valve seats on said plate concentric with said projection, an annular valve engageable with said seats, a cage for said valve overlying said plate, and a downwardly directed tubular sleeve on said 'cage encircling said projection and being encircled by said valve.

JOHN R. REPLOGLE. 

